外耳道炎を伴わなかった非典型的な頭蓋底骨髄炎の1例

A case of atypical skull base osteomyelitis without external otitis

はじめに

　典型的な頭蓋底骨髄炎は，高齢糖尿病患者に発症した緑膿菌による悪性外耳道炎を契機として頭蓋底へ炎症が波及したもので，時に致命的となりうる疾患である^1,2）。近年，それらとは所見を異にする非典型的な頭蓋底骨髄炎の報告がみられる^3〜5）。今回われわれは，外耳道炎を伴わない頭蓋底骨髄炎例を経験したので報告する。

　We report a case of atypical skull base osteomyelitis. Typical osteomyelitis is accompanied with external otitis, but recently atypical osteomyelitis which lacks external otitis was reported. A 74-year-old woman visited our hospital for left temporal headache. She had no history of diabetes, but was treated with steroids, immunosuppressive drugs and biologicals for rheumatism. She was diagnosed with nasopharyngitis and left acute otitis media；however, no external otitis was observed. CT scan revealed erosion of the midline of skull base bone. Low signal intensity was observed on T1-weighted MRI of left petrous pyramid apex. She achieved a good response to antibiotic therapy.